WO2014198182A1

WO2014198182A1 - Led fluorescent lamp driving power source and led fluorescent lamp

Info

Publication number: WO2014198182A1
Application number: PCT/CN2014/078587
Authority: WO
Inventors: 赵依军
Original assignee: Zhao Yijun
Priority date: 2013-06-09
Filing date: 2014-05-28
Publication date: 2014-12-18
Also published as: CN104235785A; EP3009740A4; US9970640B2; US20160186969A1; EP3009740A1

Abstract

An LED fluorescent lamp driving power source (10) and an LED fluorescent lamp (1) comprising the driving power source. The LED fluorescent lamp driving power source (10) comprises: an end cover (110A, 110B), a pair of plug pins (111A, 112A, 111B, 112B) being disposed on an outer surface of the end cover (110A, 110B), and the pair of plug pins (111A, 112A, 111B, 112B) being hollow and being communicated with inside of the end cover (110A, 110B); a substrate (120A, 120B) located inside the end cover (110A, 110B), a pair of leads (121A, 122A, 121B, 122B) being disposed on one of surfaces of the substrate (120A, 120B), and each of the leads (121A, 122A, 121B, 122B) being inserted in a corresponding plug pin (111A, 112A, 111B, 112B) and being fixed on an inner wall of the plug pin (111A, 112A, 111B, 112B); and an LED driving circuit module (130A, 130B), disposed on the substrate (120A, 120B) and electrically connected to the leads (121A, 122A, 121B, 122B).

Description

LED fluorescent lamp driving power supply and LED fluorescent lamp

The present invention relates to semiconductor lighting technology, and more particularly to a power supply for LED fluorescent lamps and an LED fluorescent lamp including the same. Background technique

As a new type of light source, light-emitting diodes (LEDs) are widely used in various aspects of lighting because of their energy saving, environmental protection, long life and small volume. LED is a solid-state semiconductor device capable of converting electrical energy into visible light. Its basic structure generally includes a leaded support, a semiconductor wafer with B on the support, and an encapsulation material (such as fluorescent silicone or epoxy) that seals the periphery of the wafer. Resin). The semiconductor wafer includes a PN structure. When a current passes, electrons are pushed toward the P region. In the P region, electrons and holes recombine, and then energy is emitted in the form of photons, and the wavelength of the light is determined by the material forming the PN structure. .

Compared with traditional fluorescent lamps, LED fluorescent lamps have many advantages such as high photoelectric conversion efficiency, constant brightness of the light source, no stroboscopic and no harmful heavy weight. A typical LED fluorescent tube consists of a tube body, a cover, a light board, and a drive power source, wherein the drive power source can be internal to the tube body or mounted outside the tube body.

Chinese invention patent 200920134372.8 discloses a fluorescent lamp for externally illuminating an LED power supply, which comprises an LED fluorescent lamp body, which is connected with an external LED power supply, the LED power supply comprises a PCB circuit board, a yoga input and output terminal, and a power supply box. In the PCB circuit board, the B is connected to the LED fluorescent lamp body through the PCB circuit board and the output terminal. The use of the external power supply requires a major change in the wiring of the fluorescent lamp, and the installation is not convenient.

Chinese invention patent application 201110037855.9 discloses an LED fluorescent lamp comprising a lamp tube and an end cover mounted at both ends of the lamp tube, wherein the lamp tube comprises a lamp board, a plurality of LEDs arrayed on the lamp board, and a light-emitting cover shell located above the LED A step-down constant current source module for supplying a constant current to the LED is installed in the end cover, and the positive and negative conductive terminals of the light board are connected to the output end of the step-down constant current source module. It should be pointed out that the above LED fluorescent lamp is completely designed to completely shackle the original fluorescent lamp holder. Although this is beneficial to optimize the structure and circuit design of the fluorescent lamp, it is not compatible with the existing fluorescent lamp holder. Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide an LED fluorescent lamp driving power source which has the advantages of compact structure and compatibility with existing daylight lamps.

An LED fluorescent lamp driving power supply according to an embodiment of the present invention includes:

The end cover has an outer surface provided with a pair of pins, the pair of pins being hollow and communicating with the interior of the end cap;

a substrate located in the end cover, one of the surfaces of the substrate is provided with B-pair leads, each lead is inserted into a corresponding pin and fixed to an inner wall of the pin;

An LED drive circuit module on the substrate is provided, which is electrically connected to the lead. An LED fluorescent lamp driving power supply according to another embodiment of the present invention includes:

a pair of end caps, each of the outer surfaces of the end caps is provided with a pair of pins, the pair of pins being hollow and communicating with the interior of the end cap;

a pair of substrates respectively located in respective corresponding end caps, one of each of the surfaces of the substrate is provided with a pair of leads, each of which is inserted into a pin of a corresponding end cap and fixed to an inner wall of the pin;

An LED driving circuit module is disposed on the pair of substrates and electrically connected to the leads. In the above embodiment, the LED driving circuit module can be integrated in the end cover of the ordinary fluorescent lamp, so that the structure is more compact, and the compatibility with the existing daylight lamp is also very good.

Preferably, in the above LED fluorescent lamp driving power source, the substrate further includes a pin or a socket disposed on the other surface opposite to the one surface of the substrate and electrically connected to the LED driving circuit module .

Preferably, in the above LED fluorescent lamp driving power source, wherein the inner wall of the pin is contracted inwardly to hold the lead wire therein. This lead-clamping structure can be implemented using existing fluorescent lamp production processes, helping to reduce manufacturing costs.

Preferably, in the above LED fluorescent lamp driving power source, the LED driving circuit module comprises: a bridge rectifying and filtering unit;

a DC-DC boost converter unit including an inductor, a switching diode, a PWM controller, and a MOS transistor, wherein the inductor and the switching diode are connected in series at an output end of the bridge rectifying and filtering unit and the LED driving circuit module Between the positive output terminals, the drain of the MOS transistor is electrically connected between the inductor and the positive terminal of the switching diode, and the gate is electrically connected to the output of the PWM controller;

The anti-hunger unit includes a transistor having a base electrically connected to a negative output terminal of the LED driving circuit module, and a collector electrically connected to a control end of the PWM controller.

More preferably, in the above described lamp head, the switched DC/DC converter further includes a capacitor electrically coupled between the control terminal of the PWM controller and ground.

More preferably, in the above lamp holder, the PWM controller and the MOS transistor are integrated in the same integrated circuit chip.

More preferably, within the lamp cap described above, the PWM controller, MOS transistor and transistor are integrated into the same integrated circuit chip.

The DC-DC step-down conversion unit includes an inductor, a switching diode, a PWM controller, and a MOS transistor, wherein a cathode of the switching diode and a positive output terminal of the LED driving circuit module are connected to the bridge rectifier filter An output of the cell, a drain of the MOS transistor being electrically connected to a positive electrode of the switching diode, a gate electrically connected to an output of the PWM controller, and the inductor being electrically connected to a drain of the MOS transistor Between the pole and the negative output of the LED drive circuit module;

An anti-angry unit, comprising a resistor connected to the MOS of the PWM controller The source of the tube.

More preferably, in the above LED fluorescent lamp driving power source, the LED driving circuit module further includes a capacitor electrically connected between the positive output terminal and the negative output terminal.

More preferably, in the above LED fluorescent lamp driving power source, the PWM controller and the MOS transistor are integrated in the same integrated circuit chip.

Preferably, in the LED fluorescent lamp driving power source, the LED driving circuit module includes a bridge rectifying filtering unit and a constant current control unit, wherein the constant current control unit includes an amplifier, a MOS transistor, and a first resistor, a positive output terminal of the bridge rectifier filtering unit is connected to a positive output terminal of the LED driving circuit module, and a source of the MOS transistor is electrically connected to a negative output terminal of the LED driving circuit module, and a drain of the MOS transistor Electrically coupled to a first input of the amplifier and grounded via the first resistor, an output of the amplifier being electrically coupled to a gate of the MOS transistor to be in accordance with a voltage on the drain and the amplifier The comparison of the reference voltages on the second input of the device controls the turn-on and turn-off of the MOS transistors.

Preferably, in the above LED fluorescent lamp driving power source, the constant current control unit further includes a second resistor electrically connected between the source and the drain of the MOS transistor.

In the above LED fluorescent lamp driving power source, the second resistor connected between the source and the drain of the MOS transistor can perform a better shunting function', which effectively reduces the heat generation amount of the MOS transistor, thereby improving the flow of the LED load. Current.

Preferably, in the above LED fluorescent lamp driving power source, the constant current control unit further includes a reference voltage circuit electrically connected to the second input terminal of the amplifier.

Preferably, in the above LED fluorescent lamp driving power source, the amplifier, the MOS transistor and the reference voltage circuit are integrated in the same integrated circuit chip.

Preferably, in the above LED fluorescent lamp driving power source, further comprising a filter capacitor electrically connected between the positive output terminal and the negative output terminal of the bridge rectifying filter unit.

Another object of the present invention is to provide an LED fluorescent lamp which has the advantages of compact structure and compatibility with existing daylight lamps.

An LED fluorescent lamp according to another embodiment of the present invention includes:

Tube body

a light source panel located inside the tube body, on which a plurality of LED units are disposed;

Closing a pair of end caps at both ends of the tubular body, each of the end caps is provided with a pair of pins on the outer surface thereof, the pair of pins being hollow and communicating with the interior of the end cap;

a pair of substrates respectively located in the respective corresponding end caps and fixed to the light source panel, one of the surfaces of each of the substrates is provided with a pair of leads, each of which is inserted into a corresponding end cap Inside the pin and fixed to the inner wall of the pin;

An LED driving circuit module is disposed on the pair of substrates and electrically connected to leads on one of the substrates.

Preferably, in the above LED fluorescent lamp, the light source panel and the substrate are an aluminum substrate or a double-sided printed circuit board.

Preferably, in the above LED fluorescent lamp, the LED units are connected in series, in parallel or in a hybrid manner. Coupled figure description

The above and/or other aspects and advantages of the present invention will be more clearly understood and understood from

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an exploded perspective view of an LED fluorescent lamp driving power supply in accordance with one embodiment of the present invention. 2A is an exploded perspective view showing a variation of the driving power of the LED fluorescent lamp shown in FIG. 1.

2B is an exploded perspective view showing a variation of the driving power of the LED fluorescent lamp shown in FIG. 1.

3 is an exploded perspective view of an LED fluorescent lamp driving power supply according to another embodiment of the present invention. Figure 4 is an exploded perspective view of an LED fluorescent lamp in accordance with one embodiment of the present invention.

Fig. 5 is an exploded perspective view showing a variation of the LED fluorescent lamp shown in Fig. 4.

Figure 6 is an exploded perspective view of an LED fluorescent lamp in accordance with another embodiment of the present invention.

Figure 7 is a circuit schematic diagram of an LED drive circuit module applicable to the above embodiment with the aid of Figures 1-6.

Figure 8 is a circuit diagram showing a variation of the LED drive circuit module shown in Figure 7.

Figure 9 is a circuit schematic diagram of another LED driver circuit module that can be applied to the above embodiment with the aid of Figures 1-6.

Figure 10 is a circuit diagram showing a variation of the LED drive circuit module shown in Figure 9.

Figure 11 is a circuit schematic diagram of another LED driver circuit module that can be applied to the above embodiment with the aid of Figures 1-6. detailed description

The invention will now be described more fully hereinafter with reference to the accompanying drawings However, the invention may be embodied in different forms and should not be construed as limited to the various embodiments presented herein. The above-described embodiments are intended to provide a complete and complete disclosure of the present disclosure to those skilled in the art.

In the present specification, the term "semiconductor wafer" refers to a plurality of independent single circuits, "semiconductor wafers" or "die" formed on a semiconductor material such as silicon, gallium arsenide, etc., unless otherwise specified. This refers to such a single circuit, and "packaged chip" refers to the physical structure of the semiconductor wafer after being packaged. In a typical such physical structure, the semiconductor wafer is mounted, for example, on a support and encapsulated with a sealing material.

The term "light emitting diode unit" refers to a unit comprising an electroluminescent material, examples of which include, but are not limited to, P-N junction inorganic semiconductor light emitting diodes and organic light emitting diode OLEDs and polymer light emitting diodes (PLEDs).

The PN junction inorganic semiconductor light emitting diodes can have different structural forms including, for example, but not limited to, light emitting diode dies and light emitting diode cells. Wherein, "light emitting diode die" refers to a semiconductor wafer having a PN structure and having electroluminescence capability, and "light emitting diode cell" refers to a physical structure formed by packaging a die, which is typical In a physical configuration, the die is mounted, for example, on a bracket and encapsulated with a sealing material. The terms "wiring", "wiring pattern," and "wiring" refer to conductive patterns on the insulating surface that are used for electrical connection between components, including but not limited to traces and holes (such as soldering). Disc, component hole, fastening hole and gold sharp hole, etc.).

"Electrical connection" and "coupled" are to be understood to include situations in which electrical energy or electrical signals are transmitted directly between two units, or in which electrical or electrical signals are transmitted indirectly via one or more third units.

"Drive power supply, or "LED drive power supply" refers to the "electronically controlled mounting" between an alternating current (AC) or direct current (DC) power supply connected to the outside of the lighting fixture and the light emitting diode as a light source, for The light emitting diode provides the required current or voltage (eg constant current, constant voltage or constant power, etc.). In a particular embodiment, the drive power source can be implemented in a modular configuration, for example comprising a printed circuit board and one or more mountings Components that are electrically connected together on a printed circuit board and through wiring. Examples of such components include, but are not limited to, LED driver controller chips, rectifier chips, resistors, capacitors, and inductors or coils.

The use of terms such as "including" and "comprises" or "comprises" or "comprises" or "comprising" or "comprises" The situation of the unit and the steps.

Terms such as "first", "second", "third," and "fourth" do not denote the order of the elements in terms of time, space, size, etc., but merely for distinguishing the units.

Terms such as "the object A is placed on the surface of the object B" should be broadly understood to mean that the object A is placed directly on the surface of the object B, or that the object A is placed on the surface of other objects that are in contact with the object B. . Embodiments of the invention are described below with the aid of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an exploded perspective view of an LED fluorescent lamp driving power supply in accordance with one embodiment of the present invention. As shown in Fig. 1, an LED fluorescent lamp driving power source 10 according to this embodiment includes an end cap 110, a substrate 120, and an LED driving circuit module 130.

The end cap 110 can take the form and specifications of a conventional fluorescent lamp end cap or plug. Specifically, a pair of pins 111 and 112 are provided on the outer surface of the end cap 110, for example, by riveting, and the pair of pins can serve as an electrical interface between the lamp holder and the LED fluorescent lamp driving power source. In the present embodiment, the pins 111 and 112 are hollow and are in communication with the interior space of the end cap 110.

In the completed assembled LED fluorescent lamp power supply 10, the substrate 120 is located inside the end cap 110. For example, the ordinary fluorescent lamp production process can be utilized to fix the substrate 120 in the end cap 110 while the end cap 110 is closed at both ends of the fluorescent lamp body by an adhesive such as a lamp mud. A pair of leads 121 and 122 are disposed on the lower surface of the substrate 120 as shown in FIG. The pair of leads are input to the respective input pins 111 and 112 as input terminals of the LED drive circuit module 130. The fixing and electrical connection between the lead and the pin can be achieved by holding the inner walls of the pins 111 and 112 inwardly to clamp the leads 121 and 122, respectively. To this end, existing fluorescent lamp production equipment can be utilized to squeeze the outer surface of the pin to shrink the inner wall after inserting the lead into the respective pins. In this embodiment, the lead wires may be hard wires or soft wires. Referring to FIG. 1, a pair of pins 123 and 124 are provided on the upper surface of the substrate 120. The pair of pins serve as an output of the LED drive circuit module 130 and are adapted to be electrically connected to the LED unit of the LED fluorescent lamp. Alternatively, as shown in FIG. 2A, a socket 125 may be provided on the upper surface of the substrate 120 instead of the pin in FIG. Alternatively, the output of the LED driving circuit module 130 may also be in the form of a via, such as a pair of vias 126a and 126b formed on the substrate 120 as shown in FIG. 2B.

As shown in FIG. 1, the LED driving circuit module 130 is disposed on the upper surface of the substrate 120, and includes various components and wiring for realizing electrical connection between the components. In the present embodiment, the input end of the LED driving circuit module 130 is in the form of a lead and the output end is in the form of a pin. The circuit principle of the LED drive circuit module 130 will be described in detail below.

3 is an exploded perspective view of an LED fluorescent lamp driving power supply according to another embodiment of the present invention. In the embodiment shown in Fig. 1, the LED drive circuit module is disposed on a substrate. Unlike this layout, in the embodiment shown in Fig. 3, the components of the LED drive circuit module are distributed over two substrates, as described further below.

As shown in FIG. 3, the LED fluorescent lamp driving power supply 10 according to the present embodiment includes a pair of end caps 110A and 110B, a pair of substrates 120A and 120B, and an LED driving circuit module 130, wherein the first portion 130A of the LED driving circuit module 130 ( For example, a bridge rectifier circuit) and a second portion 130B (for example, a DC-DC conversion circuit and a reverse-hungry circuit, etc.) are disposed on the substrates 120A and 120B, respectively. Preferably, the electrical connection between the first and second portions 130A and 130B can be achieved by means of electrical connection components (e.g., connecting wires or wiring formed on the light source panel) external to the LED drive power source when the fluorescent lamps are assembled.

A pair of pins 111A and 112A are disposed on the outer surface of the end cap 110A to provide an electrical interface between the socket and the LED daylight driving power source. The pins 111A and 112A are also hollow and are in communication with the interior space of the end cap 110A.

In the assembled LED fluorescent lamp driving power source 10, the substrate 120A is disposed inside the end cap 110A. As described above, the ordinary fluorescent lamp production process can be employed to fix the substrate 120A in the end cap 110A while assembling the fluorescent lamp to save the process steps. A pair of leads 121A and 122A and a pair of pins 123A and 124A are respectively disposed on the lower surface and the upper surface of the substrate 120A. The leads 121A and 122A may be hard wires or flexible wires which are respectively inserted into the respective pins 111A and 112A and held by the inner walls of the pins to realize the fixing and electrical connection between the leads and the pins, thereby Kui 120A on the substrate may be a first portion 130A and 122A, and lead pins 121A and 111A 1UA external power supply (e.g. mains ² 2 0V) are electrically connected. The pins 123A and 124A disposed on the upper surface of the substrate U0A provide an electrical connection interface with the other components (e.g., the second portion 130B) for the first portion 130A of the LED drive circuit module. In the present embodiment, the pin can also be replaced with a slot similar to that shown in FIG. 2A or the via shown in FIG. 2B.

For the end cap 110B and the substrate 120B disposed therein, they have substantially the same or similar structures and features as the end cap 110A and the substrate 120A, and therefore the differences are described here. Specifically, the leads 121B and 122B provided with the turns on the substrate 120B are inserted into the corresponding pins 111B and 112B and held by the inner walls of the pins, but the leads 121B and 122B are not connected to the second portion 130B of the LED drive circuit module. . Preferably, the leads 121B and 122B can be shorted together, thereby The pins 111B and 112B are directly connected to facilitate the installation of the LED fluorescent lamp. In addition, the substrate 120B is provided with four pins, two of which can be electrically connected to the pins 123A and 124A on the substrate 120A via the wiring on the light source board, and the other two serve as the output end and the light source of the LED driving circuit module 130. The LED units on the board are electrically connected. Due to the view angle, only the pin 123B in which the pin 123A is electrically connected is shown in FIG. Again, the pins here can be replaced by slots or vias.

It should be noted that although in the embodiment shown in FIG. 1-3 above, the LED driving circuit module is only disposed on one surface of the substrate, alternatively, it may be disposed on the upper and lower sides of the substrate. On the surface.

4 is an exploded perspective view of an LED fluorescent lamp in accordance with another embodiment of the present invention.

The LED fluorescent lamp 1 shown in Fig. 4 includes an LED driving power source 10, a light source module 20, and a tube body 30. For the sake of convenience, the light source panel of the light source module and the intermediate portion of the tube body are not shown in Fig. 4, but this does not affect the understanding of the text content.

The LED driving power source 10 can be disposed at both ends of the tube body 30 by the structure and features shown above with reference to FIG. The light source module 20 includes a light source board 210 located in the tube body 30, an LED unit 220 disposed on the light source board, and sockets 230A and 230B disposed at two ends of the light source board, wherein the plurality of LED units on the light source board 210 can be connected in series Connected in parallel, in parallel, in a hybrid or cross array.

Further, it should be understood that FIG. 4 is a schematic view in an exploded state, and when the LED fluorescent lamp 1 is assembled, the end caps 110A and 110B of the LED driving power source 10 will close both ends of the tubular body 30. In the present embodiment, the inner surfaces of the end caps 110A and 110B can be bonded to the outer surface of the tube body 30 by means of an adhesive such as a lamp paste, and at the same time, the substrate is fixed in the end cap.

When the LED fluorescent lamp 1 is assembled, the substrates 120A and 120B and the light source panel 210 can be fixed together by means of the illustrated pins and sockets and thereby electrical connection of the LED driving circuit module to the LED unit. At the same time, suitable wiring (not shown) is formed on the light source panel 210 to electrically connect between the first and second portions 130A and 130B of the LED driving circuit modules on different substrates. Similar to the embodiment described with reference to Fig. 3, the substrate 120B is provided with four pins, two of which are electrically connected to the pins 123A and 124A on the substrate 120A via the wiring on the light source board, and the other two are driven as LEDs. The output of circuit module 130 is electrically coupled to LED unit 220. Due to the view angle, only the pin 123B in which the pin 123A is electrically connected is shown in Fig. 4.

Alternatively, the substrate of the LED driving power source 10 and the light source panel of the light source module 20 may also be joined by a card slot. Fig. 5 is an exploded perspective view showing a variation of the LED fluorescent lamp shown in Fig. 4, showing the above-described card slot engagement mode. For the sake of convenience, the light source panel of the light source module and the intermediate portion of the tube body are not shown in FIG. 5, but this does not affect the understanding of the text content. As shown in FIG. 5, the substrates 120A and 120B are respectively provided with the slots 125A and 125B, and at the same time, the two ends of the light source panel 210 are respectively formed with wirings 240A and 240B, and the two ends of the light source panel 20 are inserted into the slots 125A and 125B. In the meantime, on the one hand, the light source board and the substrate 110A and 110B can be fixed together. On the other hand, the LED driving circuit module on the substrate can be electrically connected with the LED unit, and the LED driving circuit module on the different substrate is the first The first and second portions 130A and 130B can also be electrically connected together via suitable wiring (not shown) formed on the light source panel. Specifically, as shown in FIG. 5, the wiring 240B includes four finger-shaped branches, two of which pass through the wiring on the light source board and two points on the wiring 240A. The electrical connections are made, and the other two are electrically connected to the LED unit 220 as an output of the LED driving circuit module 130.

Alternatively, the substrate of the LED driving power source 10 and the light source panel of the light source module 20 may be fixed together in the form of a via as shown in Fig. 2B. Specifically, a via hole is formed on the substrate 120A and 120B, and both ends of the light source panel 210 form a finger-shaped protruding portion adapted to the via hole, and the substrate and the light source panel can be formed by soldering the finger-shaped protruding portion in the via hole. Fixed together.

In the present embodiment, the tubular body 30 may be made of glass or plastic. In order to avoid the glare effect, at least one of the inner surface and the outer surface of the tube formed of glass may be frosted (e.g., the inner tube surface is roughened using an acid solution). Alternatively, it is also conceivable to apply a light diffusion powder to the inner surface of the tube body 30.

Unlike the embodiment shown in Figs. 4 and 5, in the present embodiment, the LED driving circuit module of the LED driving power source is disposed on a substrate, and accordingly, the LED driving power source is located at one end of the tube body. To avoid the above description, the differences between the present embodiment and the foregoing embodiments will be mainly described below.

The LED fluorescent lamp 1 according to the embodiment shown in Fig. 6 includes an LED driving power source 10, a light source module 20, and a tube body 30. For the sake of convenience, the light source panel of the light source module and the middle portion of the tube body are omitted in Fig. 6, but this does not affect the understanding of the text content.

The LED driving power source 10 can be disposed at one end of the tube body 30 by the structure and features shown above with reference to FIG. The light source module 20 employs the same structure and features as the embodiment shown in Fig. 4, but the structure and features of the embodiment shown in Fig. 5 can also be employed.

When the LED fluorescent lamp 1 is assembled, the end cover 110 of the LED driving power supply 10 fixes the one end of the tubular body 30 and the light source plate 210 by means of the card slot shown in the figure and thereby achieves Electrical connections.

In the present embodiment, the LED fluorescent lamp 1 further includes an end cap 410 and a substrate 420 located in the end cap 410. As shown in Fig. 6, the outer surface of the end cap 410 is provided with a pair of pins 411 and 412 adapted to be inserted into the fluorescent lamp holder. When the LED fluorescent lamp 1 is assembled, the other end of the tubular body 30 is closed by the end cap 410. For example, the inner surface of the end cap 410 can be bonded to the outer surface of the tubular body 30 by means of an adhesive such as a lamp paste, and at the same time, the substrate 420 is also fixed in the end cap 410. A pair of leads 421 and 422 and a card slot 423 are respectively disposed on both surfaces of the substrate 420. In the present embodiment, the pins 411 and 412 are also hollow and in communication with the inner space of the end cap 410, so that the leads 421 and 422 are respectively inserted into the respective corresponding pins 411 and 412 and held by the inner wall of the prong, thereby A fixed and electrical connection between the leads and the pins is achieved. When the assembly of the fluorescent lamp 1 is completed, the pins 423A and 423B on the substrate 420 are inserted into the socket 230B at one end of the light source panel 210 to fix the light source panel 210 and the substrate 420 together. Preferably, leads 421 and 422 are shorted together to effect a direct connection between pins 411 and 412.

The LED driving circuit module 130 shown in FIG. 7 includes a bridge rectifying filtering unit 131, a DC-DC boost converting unit 132A, and an anti-inversion unit 133, which are further described below. As shown in FIG. 7, the bridge rectification filtering unit 131 includes a full bridge rectifier BR1, capacitors C1, C2, C3, a varistor R1, and an inductor L1. The alternating current (for example, mains) is rectified by the full-bridge rectifier BR1 and then outputs a full-wave ripple voltage on the positive terminal B1. The filter capacitors Cl, C2, C3, varistor R1 and inductor L1 constitute an EMI filter circuit, which on the one hand suppresses the influence of high frequency interference in the AC power grid on the drive circuit, and on the other hand suppresses the electromagnetic circuit of the drive circuit to the AC grid. interference.

It is worth noting that although full-wave rectification is shown here, half-wave rectification is also available. Further, in order to further simplify the circuit structure, the varistor R1, the smoothing capacitors C2, C3, and the inductor L1 in the bridge rectifying and filtering unit 131 of the circuit shown in Fig. 7 can also be omitted.

Referring to Figure 7, the smoothing capacitor C1 and the varistor R1 are connected in parallel between the AC input terminals B3 and B4 of the full bridge rectifier BR1, wherein the varistor R1 passes the full bridge rectifier BR1 by suppressing abnormal overvoltages present in the circuit. The input voltage is clamped at a predetermined level. The filter capacitors C2, C3 and inductor L1 form a π-type filter loop and are electrically connected between the positive terminal B1 and the negative terminal Β2 of the full-bridge rectifier BR1 to low-pass filter the ripple voltage output from the full-bridge rectifier BR1.

The DC-DC boost conversion unit 132A is electrically connected to the bridge rectification filtering unit 131, the anti-inversion unit 133, and the LED loads LED1-LEDn (that is, the plurality of LED units 220 disposed on the light source panel in FIGS. 4-6). It boosts the ripple voltage output by the bridge rectifier filtering unit 131 to the required voltage and current levels and provides it to the LED load. In addition, the DC-DC boost converter unit 132A also cooperates with the reverse anger unit 133 to keep the current and voltage supplied to the LED load constant and to implement a power factor correction function. In a typical application, the total voltage of multiple LED units connected in series is designed to exceed the maximum voltage of the grid input, so voltage boosting is required. For example, for a 220V AC with a fluctuation range of ±10%, the maximum voltage is about 342V, and the LED series voltage will exceed 342V.

In the LED drive circuit module shown in Fig. 7, the DC-DC boost converter unit 132A includes an inductor L2, a switching diode D1, a capacitor C6, and a switching regulator Ul.

Preferably, an integrated circuit chip integrated with a pulse width modulation (PWM) controller and a gold-solder oxide semiconductor field effect transistor (hereinafter also referred to as a MOS transistor) may be used as the switching regulator U1, wherein the output of the PWM controller is The gate of the MOS transistor is electrically connected to control the turn-on and turn-off of the MOS transistor. In the specific switching regulator chip, in order to simplify the adjustment of the duty ratio, the switching frequency of the MOS transistor can be kept constant (for example, about 1 MHz), and the turn-off time of the MOS transistor can be adjusted; or the MOS transistor can be maintained. off-time is a fixed value (e.g., about 3 ² 0ns), and the switching frequency of the MOS transistor is adjustable. Typically, such switching regulator chips are typically provided with a drain pin that is electrically coupled to the drain of the MOS transistor and an inverted polarity pin that is electrically coupled to the control terminal of the PWM controller. Examples of the above switching regulator include, but are not limited to, CW12L30 and CW12L40 chips produced by China Puxinda Electronics Co., Ltd.

As shown in FIG. 7, the inductor L2 and the switching diode D1 are connected in series between the output of the bridge rectifying and filtering unit 131 and the positive input terminal of the LED load or the positive output terminal of the LED driving circuit module, wherein the positive electrode of the switching diode D1 It is electrically connected to the inductor L2, and the negative electrode is electrically connected to the positive input terminal of the LED load. Preferably, a Schottky diode having a fast speed and a small voltage drop can be employed as the switching diode D1. Continuing to refer to FIG. 7, the drain pin D of the switching regulator U1 is electrically connected between the inductor L2 and the anode of the switching diode D1, and the counter debt pin FB is electrically connected to the anti-hungry unit 133. This In addition, in the circuit shown in FIG. 7, the capacitor C6 and the positive input terminal of the LED load are connected to the negative terminal of the switching diode D1 to discharge the LED load when the switching diode D1 is turned off.

Referring to Figure 7, the switching regulator U1 also includes a power pin VCC and a ground pin GND, wherein the power pin VCC is grounded via capacitor C4.

The anti-angry unit 133 includes a transistor Q1, resistors R2, R3, and a capacitor C5. As shown in FIG. 7, the transistor Q1 adopts a connection form of a common emitter amplifying circuit, wherein the collector is electrically connected to the reverse polarity pin of the switching regulator U1 via the resistor R3 to provide an inverted signal to the switching regulator U1. The emitter is electrically connected to the ground as a common ground of the input loop and the output loop, and the base is connected to the loop of the LED load by electrical connection with the cathode of the LED load to extract the detection signal. Resistor R2 is electrically connected between the base and ground to form an input loop. In addition, the reverse polarity pin FB of the switching regulator U1 is also grounded via capacitor C5.

The operation of the LED drive circuit module 130 shown in Fig. 7 will be described below.

When the AC power is turned on, the bridge rectification filtering unit 131 converts the input AC power into a ripple voltage and outputs it to the inductor L2 of the DC-DC boost converter unit 132A. Switching regulator The MOS transistor inside U1 is turned on and off at a high frequency under the control of the PWM controller signal.

When the MOS is turned on, current flows through the inductor L2 and the MOS transistor under the action of the output voltage of the bridge rectifying and filtering unit 331, and the switching diode D1 is turned off due to the voltage on the capacitor C6. As the current flowing through the inductor L2 continues to increase, the energy stored in the inductor is also constantly increasing. At this time, the LED load is supplied by the capacitor C6, which operates by the discharge current of the capacitor C6.

When the MOS transistor is switched to the off state, the current flowing through the inductor L2 starts to decrease, thereby inducing an induced electromotive force at both ends of the inductor L2, the polarity of which is upper right and right negative. The induced electromotive force is superimposed with the output voltage of the bridge type rectification filtering unit 131 to increase the output voltage of the bridge rectifying and filtering unit 131. At this time, the superimposed voltage is higher than the voltage on the capacitor C6, so the switching diode D1 enters an on state, the LED load is powered by the inductor L2, and the capacitor C6 is also charged by the inductor L2 and until the MOS transistor is switched again to conduct. status. In the present embodiment, the magnitude of the induced electromotive force depends on the duty ratio of the MOS transistor, so that the desired voltage boosting amplitude can be obtained by adjusting the duty ratio of the output signal of the PWM controller.

When the MOS transistor is switched back to the on state again, the superimposed voltage at the switching diode D1 begins to decrease and will again fall below the voltage on the capacitor C6, so the switching diode D1 enters an off state, and the LED load is changed by the capacitor C6 to be lifted. The voltage is supplied and the inductor L2 begins to store electrical energy.

It can be seen from the above that under the control of the PWM controller, the MOS transistor is continuously switched between the above-mentioned on and off states, so that the voltage on the positive pole of the LED load is always maintained at a relatively high voltage level.

Referring to Figure 7, the LED load is connected in parallel with the resistors R4 and R5 in the negative direction of the switching diode D1 and the resistor R2, and the negative pole of the LED load is electrically connected to the base of the transistor Q1. When the current and/or voltage flowing through the LED load fluctuates, the current flowing through the base of the transistor Q1 also changes, and the inverted anger signal amplified by the transistor Q1 is output from the collector via the resistor R3 to the switch adjustment. The anti-inverted pin of U1, the PWM controller can thereby adjust the duty cycle of the output signal according to the anti-angry signal, thereby keeping the current and voltage supplied to the LED load constant.

In the circuit shown in FIG. 7, the reverse polarity pin FB of the switching regulator U1 is also subjected to a large-capacity capacitor. C5 is grounded, which slows the response of the anti-angry loop, which is nearly constant during the half cycle of the AC line. A substantially constant level of reversal indicates that the current in the MOS tube corresponds to the average energy delivered to the LED load during the half cycle of the AC line. Since the switching regulator U1 operates at a fixed frequency, the current does not increase beyond a certain range until the MOS transistor is turned on. By reducing the switching current flowing through the MOS transistor when the input AC voltage is applied, and increasing the switching current flowing through the MOS transistor when the input AC voltage is reduced, the ripple at the LED load input terminal is minimized, and the AC input current is minimized. The power factor correction function can be realized by constantly tracking changes in the AC input voltage.

It should be noted that in the circuit shown in FIG. 7, the PWM controller and the MOS transistor are integrated in the same integrated circuit chip. In order to further improve the integration degree, the transistor Q1, the PWM controller and the MOS transistor can also be considered. Integrated in the same integrated circuit chip.

Alternatively, the PWM controller and the MOS transistor may also be provided in the LED driver circuit module in the form of discrete circuit components. The LED drive circuit module shown in Fig. 8 shows an example of this form, and the same or similar elements as those in Fig. 7 are denoted by the same reference numerals.

The drive circuit module 130 shown in Fig. 8 also includes a bridge rectification filter unit 131, a DC-DC boost conversion unit 132A, and an anti-inversion unit 133. The bridge rectification filtering unit 131 and the anti-starving unit 133 adopt the same form and structure as those shown in Fig. 7, and will not be described again here.

Referring to FIG. 8, the DC-DC boost converter unit 132A includes an inductor L2, a switching diode D1, a capacitor C6, a PWM controller U2, and a MOS transistor T, wherein the inductor L2 and the switching diode D1 are connected in series to the bridge rectifier filtering unit. The output of the 131 is connected to the positive input of the LED load or the positive output of the LED drive module. The positive terminal of the switching diode D1 is electrically connected to the inductor L2, and the negative electrode is electrically connected to the LED load. In this embodiment, the drain D of the MOS transistor T is electrically connected between the inductor L2 and the anode of the switching diode D1, the source S is electrically connected to the ground, and the gate G is connected to the output terminal P of the PWM controller U2. The PWM controller U2 is generally provided in the form of an integrated circuit chip, and its control terminal FB is electrically connected to the reverse anger unit 333. As shown in Fig. 8, the capacitor C6 is electrically connected between the negative electrode of the switching diode D1 and the LED load to discharge the LED load when the switching diode D1 is turned off.

The anti-hunce unit 133 also includes a transistor Q1, resistors R2, R3, and a capacitor C5. The transistor Q1 adopts a connection form of a common emitter amplifying circuit, wherein the collector is electrically connected to the control terminal FB of the PWM controller U2 via a resistor R3 to provide an inverted signal to the PWM controller U2, the emitter and the grounding electrical The connection is used as a common ground for the input loop and the output loop, and the base is connected to the loop of the LED load to extract the detection signal. The control terminal FB of the PWM controller is also grounded via capacitor C5.

The operation principle of the LED driving circuit module shown in Fig. 8 is similar to that shown in Fig. 7, and therefore will not be described here.

The LED driving circuit module 130 shown in FIG. 9 includes a bridge rectifying filtering unit 131, a DC-DC step-down converting unit 132B, and an anti-hunting unit 133, which are further described below. As shown in FIG. 9, the bridge rectification filtering unit 131 includes a full bridge rectifier BR1, capacitors C2, C3, a varistor R1, and an inductor L1. The alternating current (for example, mains) is rectified by the full bridge rectifier BR1 and outputs a full-wave ripple voltage on the positive terminal B1. The filter capacitors C2, C3, the varistor R1 and the inductor L1 constitute an EMI filter circuit, which on the one hand suppresses the influence of high frequency interference in the AC power grid on the drive circuit, and on the other hand suppresses the electromagnetic interference of the drive circuit to the AC grid.

Referring to FIG. 9, the varistor R1 is connected in parallel between the AC input terminals B3 and B4 of the full-bridge rectifier BR1, wherein the varistor R1 clamps the input voltage of the full-bridge rectifier BR1 by suppressing an abnormal overvoltage occurring in the circuit. At the predetermined level. The filter capacitors C2, C3 and inductor L1 form a π-type filter loop and are electrically connected between the positive terminal B1 of the full-bridge rectifier BR1 and the negative terminal Β2 of the ground to low-pass filter the ripple voltage output from the full-bridge rectifier BR1.

It is worth noting that although full-wave rectification is shown here, half-wave rectification is also available. Further, in order to further simplify the circuit structure, the varistor R1, the filter capacitors C2, C3, and the inductor L1 in the bridge rectifying and filtering unit 131 of the circuit shown in Fig. 9 can also be omitted.

The DC-DC step-down conversion unit 132B is electrically connected to the bridge rectification filtering unit 131, the anti-angry unit 133, and the LED load LED1-LEDn (for example, the LED unit 220 provided on the light source panel 210 in FIGS. 4-6), which will bridge The ripple voltage output by the rectification filtering unit 131 is reduced to a desired voltage and current level and supplied to the LED load. In addition, DC-DC buck conversion unit 132B also cooperates with anti-aggression unit 133 to maintain a constant current and voltage supplied to the LED load.

In the LED drive circuit module shown in FIG. 9, the DC-DC step-down conversion unit 132B includes an inductor L ² , a switching diode D1, a capacitor C, a MOS transistor T, and a pulse width modulation (PWM) controller U3.

The output terminal P of the PWM controller U3 is electrically connected to the gate G of the MOS transistor T to control the turn-on and turn-off of the MOS transistor. Examples of the above PWM controller include, but are not limited to, the HV9910 type LED driver chip manufactured by Supertex Corporation of the United States.

As shown in FIG. 9, the negative electrode of the switching diode D1 and the positive electrode LED of the LED load or the positive output terminal of the LED driving circuit module are connected in common to the output end of the bridge rectifying and filtering unit 131, and the positive electrode of the switching diode D1 is connected to the MOS transistor T. The drain D is electrically connected. Preferably, a Schottky diode having a fast speed and a small voltage drop can be employed as the switching diode D1. Inductor L2 is electrically connected between the negative LED of the LED load and the drain D of the MOS transistor T. Continuing to refer to Figure 9, the PWM controller U3 also includes an anti-angry pin FB that is electrically coupled to the anti-angry unit 133. In addition, in the circuit shown in FIG. 9, the capacitor C7 is connected in parallel to the positive LED+ and the negative LED of the LED load (ie, the anode output and the negative output of the LED driving circuit module are smoothly supplied to the LED). Operating voltage of the load The capacitance value of capacitor C7 can be selected according to the ripple value of the permissible operating voltage.

Referring to Figure 9, the PWM controller U3 also includes a power pin VCC and a ground pin GND, where the power pin VCC is grounded via capacitor C4.

The anti-starving unit 133 includes a resistor R6. As shown in FIG. 9, the resistor R6 is electrically connected between the source S of the MOS transistor T and the ground. On the other hand, one end of the resistor R6 electrically connected to the source S is also electrically connected to the reverse polarity pin FB of the PWM controller U3 to supply an inverted flag signal to the PWM controller U3. The operation of the LED drive circuit module 130 shown in Fig. 9 will be described below.

When the AC power is turned on, the bridge rectifying filtering unit 131 converts the input alternating current into a ripple voltage and outputs it to the DC-DC step-down converting unit 132B. At this time, under the control of the PWM controller U3, the MOS transistor T is continuously switched between the above-mentioned on and off states, so that the voltage across the LED load is always maintained at a certain voltage level.

Specifically, when the MOS transistor T is turned on, the switching diode D1 is in an off state. The output current of the bridge type rectifying and filtering unit 131 flows from the positive LED + of the LED load and flows from the negative LED to the inductor L2. The current flowing through the inductor L2 will continue to increase until the MOS transistor T is turned off. As the current flowing through the inductor L2 continues to increase, the energy stored in the inductor is also constantly increasing.

When the MOS transistor T is switched to the off state, the current flowing through the inductor L2 starts to decrease, thereby inducing an induced electromotive force at both ends of the inductor L2, the polarity of which is left positive and right negative. The induced electromotive force is superimposed on the output voltage of the bridge rectification filtering unit 131 and is higher than the voltage on the capacitor C7, so the switching diode D1 enters an on state, thereby providing a freewheeling path for the current of the inductor L2 until the MOS transistor T is switched again. On state. In the circuit configuration shown in Figure 9, the desired voltage reduction can be obtained by adjusting the duty cycle of the PWM controller output signal.

Referring to Figure 9, resistor R6 is electrically connected between source S of MOS transistor T and ground. Since the voltage across resistor R6 corresponds to the current flowing through MOS transistor T and inductor L2, this voltage can be applied to the anti-hunger pin FB of PWM controller U3 as an anti-angry signal. Specifically, when the MOS transistor T is turned on, the current of the inductor L2 is continuously increased. When the voltage across the resistor R6 exceeds a preset peak current detection threshold, the PWM controller U3 is triggered to output on the pin P. The control signal of the MOS transistor T is turned off, whereby constant current control can be realized by controlling the peak current of the MOS transistor T. Obviously, the time it takes to reach the peak current is related to the inductance of the inductor L2. The larger the inductor value, the slower the current rise rate and the longer it takes to reach the peak current, and vice versa.

It should be noted that since capacitor C7 is connected in parallel between the LED loads as shown in Fig. 9, the ripple of the current can be smoothed, so that the current flowing through the LED load is more constant.

Alternatively, the PWM controller U3 and the MOS transistor T may be provided in the LED driver circuit module in the form of being integrated in the same integrated circuit chip. The LED drive circuit module shown in Fig. 10 shows an example of this form, and the same or similar elements as those in Fig. 9 are denoted by the same reference numerals.

The LED drive circuit 130 shown in Fig. 10 also includes a bridge rectification filtering unit 131, a DC-DC step-down conversion unit 132B, and an anti-inversion unit 133. The bridge rectification filtering unit 131 and the anti-starving unit 133 adopt the same form and structure as those shown in Fig. 9, and are not described herein again.

The DC-DC step-down conversion unit 132B is electrically connected to the bridge rectification filtering unit 131, the anti-inversion unit 133, and the LED loads LED1-LEDn, which reduces the ripple voltage output from the bridge rectification filtering unit 131 to a desired voltage and current level. And to provide LED load. In addition, DC-DC buck conversion unit 132B also cooperates with anti-aggression unit 133 to maintain a constant current and voltage supplied to the LED load.

In the LED drive circuit shown in Fig. 10, the DC-DC step-down conversion unit 132B includes an inductor L2, a switching diode D1, a capacitor C7, and a switching regulator U4.

Preferably, an integrated circuit integrated with a pulse width modulation (PWM) controller and a MOS transistor can be used The chip acts as a switching regulator U4, wherein the output of the PWM controller is electrically coupled to the gate of the MOS transistor to effect control of turn-on and turn-off of the MOS transistor. Typically, such switching regulator chips are typically provided with a drain pin that is electrically coupled to the drain of the MOS transistor and a source pin that is electrically coupled to the source of the MOS transistor, and preferably, the source pin is The control terminal of the PWM controller is electrically connected to invert the detection signal corresponding to the current flowing through the MOS transistor to the PWM controller. Examples of the above switching regulator include, but are not limited to, the SSL2108X type LED lighting driver chip manufactured by NXP Semiconductors of the Netherlands.

As shown in Fig. 10, the cathode of the switching diode D1 and the anode LED+ of the LED load are connected in common to the output of the bridge rectifier filtering unit 131, and the anode of the switching diode D1 is electrically connected to the drain pin D of the switching regulator U4. Inductor L2 is electrically connected between the negative LED of the LED load and the drain pin D of the switching regulator U4. Continuing to refer to Figure 10, the switching regulator U4 also includes a source pin S that is electrically coupled internally to the control terminal of the PWM controller and externally to the anti-angry unit 433 outside the chip. Further, in the circuit shown in Fig. 10, the capacitor C7 is connected in parallel between the positive LED+ and the negative LED of the LED load to smooth the operating voltage supplied to the LED load.

Referring to Figure 10, the switching regulator U4 includes a power pin VCC and a ground pin GND, wherein the power pin VCC is grounded via capacitor C4.

The anti-hunce unit 133 includes a resistor R6 electrically connected between the source S of the switching regulator U4 and the ground. As indicated in the description of the LED drive circuit module shown in FIG. 9, the voltage across the resistor R6 corresponds to the current flowing through the MOS transistor and the inductor L2, which is applied as a counter-increment signal to the source of the switching regulator U4. The pole S is such that the PWM controller inside the switching regulator U4 realizes constant current control by controlling the peak current of the MOS transistor. The operation principle of the LED driving circuit shown in Fig. 10 is similar to that shown in Fig. 9, and therefore will not be described again here.

Optionally, circuits for implementing other functions, such as a dimming control circuit, a sensing circuit, an intelligent lighting control circuit, a communication circuit, and a protection circuit, may be integrated in the LED driving circuit module shown in FIG. 7-10. These circuits may be integrated in the same semiconductor wafer or packaged chip as the drive controller, or these circuits may be provided separately in the form of semiconductor wafers or packaged chips, or some or all of these circuits may be combined together and on a semiconductor wafer or Available in the form of a packaged chip.

Figure 11 is a circuit schematic diagram of another LED driver circuit module that can be applied to the above embodiment with the aid of Figures 1-6.

The LED drive circuit module 130 shown in Fig. 11 includes a bridge rectification filter unit 131 and a constant current control unit 134, which will be further described below.

As shown in FIG. 11, the bridge rectification filtering unit 131 includes a full bridge rectifier BR1, a smoothing capacitor C1, and a varistor R1. The AC power (for example, the mains) is rectified by the full-bridge rectifier BR1 and then outputs a full-wave ripple voltage on the bridge rectifier filter unit or the positive output terminal B1 of the full-bridge rectifier BR1. The varistor R1 is connected in parallel between the bridge rectifier filtering unit or the AC input terminals B3 and B4 of the full-bridge rectifier BR1, which clamps the input voltage of the full-bridge rectifier BR1 to a predetermined value by suppressing an abnormal overvoltage occurring in the circuit. Level. The filter capacitor C1 is electrically connected between the positive output terminal B1 and the negative output terminal B2 of the bridge rectifier filter unit or the full bridge rectifier BR1 to low-pass filter the ripple voltage outputted by the full bridge rectifier BR1, where the negative output terminal B2 Grounded. It is worth noting that although full-wave rectification is shown here, half-wave rectification is also available. Further, in order to further simplify the circuit configuration, the varistor R and the smoothing capacitor C1 in the bridge rectifying and filtering unit 131 of the circuit shown in Fig. 11 can also be omitted.

The constant current control unit 134 includes a reference voltage circuit 1341, an amplifier 1342, a MOS transistor T, a first resistor R7, and a second resistor R8. Referring to FIG. 11, the LED load LED1-LEDn (for example, the LED unit 220 disposed on the light source panel 210 in FIGS. 4-6) is connected between the bridge filtering unit 131 and the constant current control unit 134, wherein the LED load LED1-LEDn The positive LED+ is electrically connected to the positive output B1 and its negative LED is electrically connected to the source S of the MOS transistor T, while the drain D of the MOS transistor T is grounded via the first resistor R7, thereby forming a current loop. The gate G of the MOS transistor T is electrically connected to the output of the amplifier 1342, and the drain D is electrically connected to the first input of the amplifier 1342 (for example, the inverting input terminal) in addition to being electrically connected to the first resistor R7. Thereby, the sampling signal VR1 across the first resistor R7 is applied to the intrusion terminal. In another aspect, the reference voltage circuit is electrically coupled to a second input of amplifier I ³⁴² (eg, a non-inverting input +) to apply a reference voltage Vref to the input. As shown in FIG. 11, a second resistor R8 is electrically connected between the source S and the drain D of the MOS transistor T.

Preferably, the reference voltage circuit, the amplifier and the MOS transistor can be integrated in the same integrated circuit chip. Examples of such integrated circuit chips include, but are not limited to, the CW11L01 chip produced by Shanghai Puxinda Electronics Co., Ltd.

In the LED driving circuit module shown in FIG. 11, the MOS transistor T itself has a certain internal resistance, so the second resistor R8 connected between the source S and the drain D of the MOS transistor T is equivalent to the MOS transistor T. A resistor is connected in parallel with the internal resistance, so that the current flowing through the LED load LED1-LEDn does not all flow into the MOS transistor T, but a part is shunted to the second resistor R8, thereby reducing the heat generation of the MOS transistor. Alternatively, the operating current of the LED load can be increased in the case of a MOS tube using the same electrical parameters.

The operation of the constant current control unit 134 is described below.

Referring to FIG. 1, the difference between the signals applied to the two input terminals of the amplifier 1342 is amplified to form a gate voltage signal on the gate G of the MOS transistor T to control the turn-on and turn-off of the MOS transistor T3⁄4, thereby flowing through The LED load LED1-LEDn has a constant current. Specifically, when the current flowing through the LED load LED1-LEDn causes the sampling signal V _R1 across the first resistor R7 to be greater than the reference voltage, the amplifier 1342 will apply a low level signal on the gate G to turn off the MOS transistor T. At this time, the resistance value of the current loop is large, so that the current flowing through the LED load LED1-LEDn is decreased; conversely, when the current flowing through the LED load LED1-LEDn is such that the sampling signal V _R1 across the first resistor R7 is smaller than At the reference voltage, the J3⁄4 amplifier 1342 will apply a high level signal on the gate G to turn on the MOS transistor T, at which time the resistance value of the current loop is small, so that the current flowing through the LED loads LED1-LEDn is large. The current flowing through the LED loads LED1-LEDn will thus remain substantially constant. While some aspects of the present invention have been shown and described, it will be understood by those skilled in the art that the invention may be modified without departing from the spirit and scope of the invention. Equivalent content is limited.

Claims

Rights request

1. An LED fluorescent lamp driving power supply, including:

The end cap has a pair of pins on its outer surface, the pair of pins are hollow and communicate with the inside of the end cap;

A substrate located in the end cap, with a pair of leads provided on one surface of the substrate, each lead inserted into its corresponding pin and fixed to the inner wall of the pin;

An LED driving circuit module is provided on the substrate and is electrically connected to the lead.

2. An LED fluorescent lamp driving power supply, which is characterized by including:

A pair of end caps, the outer surface of each end cap is provided with a pair of pins, the pair of pins are hollow and communicate with the interior of the end cap;

A pair of substrates, which are respectively located in corresponding end caps. A pair of leads are provided on one surface of each substrate, and each lead is inserted into the pin of the corresponding end cap and fixed to the inner wall of the pin; and

An LED driving circuit module is provided on the pair of substrates and is electrically connected to the leads.

3. The LED fluorescent lamp driving power supply according to claim 1 or 2, wherein the substrate further includes pins or slots, which are provided on the other surface opposite to the one surface of the substrate and are connected to the other surface. The LED driver circuit module is electrically connected.

4. The LED fluorescent lamp driving power supply as claimed in claim 1 or 2, wherein the inner wall of the pin shrinks inward to clamp the lead inside it.

5. The LED fluorescent lamp driving power supply as claimed in claim 1 or 2, wherein the LED driving circuit module includes:

Bridge rectifier and filter unit;

The DC-DC boost conversion unit includes an inductor, a switching diode, a PWM controller and a MOS tube, wherein the inductor and switching diode are connected in series between the output end of the bridge rectifier filter unit and the LED drive circuit module between the positive output terminals, the drain terminal of the MOS tube is electrically connected between the inductor and the positive terminal of the switching diode, and the gate terminal is electrically connected to the output terminal of the PWM controller; and

The reaction unit includes a transistor, the base of which is electrically connected to the negative output terminal of the LED drive circuit module, and the collector is electrically connected to the control terminal of the PWM controller.

6. The LED fluorescent lamp driving power supply as claimed in claim 5, wherein the DC/DC boost conversion unit further includes a capacitor electrically connected between the control end of the PWM controller and ground.

7. The LED fluorescent lamp driving power supply as claimed in claim 1, wherein the LED driving circuit module includes:

Bridge rectifier and filter unit;

The DC-DC step-down conversion unit includes an inductor, a switching diode, a PWM controller and a MOS tube, wherein the cathode of the switching diode and the anode output end of the LED drive circuit module are commonly connected to the bridge rectifier filter. The output end of the unit, the drain of the MOS tube is electrically connected to the anode of the switching diode, the gate is electrically connected to the output end of the PWM controller, and the inductor The device is electrically connected between the drain of the MOS tube and the negative output terminal of the LED drive circuit module; and

The reaction unit includes a resistor, which is commonly connected to the source of the MOS tube with the control end of the PWM controller.

8. The LED fluorescent lamp driving power supply according to claim 1, wherein the LED driving circuit module includes a bridge rectifier filter unit and a constant current control unit, wherein the constant current control unit includes an amplifier, a MOS tube, a first resistor, the positive output end of the bridge rectifier filter unit is connected to the positive output end of the LED drive circuit module, the source of the MOS tube is electrically connected to the negative output end of the LED drive circuit module, the The drain of the MOS tube is electrically connected to the first input terminal of the amplifier and grounded via the first resistor, and the output terminal of the amplifier is electrically connected to the gate of the MOS tube to adjust according to the The comparison result between the voltage and the reference voltage on the second input terminal of the amplifier controls the turn-on and turn-off of the MOS tube.

9. The LED fluorescent lamp driving power supply as claimed in claim 8, wherein the constant current control unit further includes a second resistor electrically connected between the source and drain of the MOS tube.

10. An LED fluorescent lamp, including:

tube body;

A light source plate located inside the tube body, with a plurality of LED units arranged on it;

A pair of end caps closing both ends of the pipe body, each end cap is provided with a pair of pins on its outer surface, the pair of pins are hollow and communicate with the interior of the end cap;

A pair of substrates, which are respectively located in corresponding end caps and fixed together with the light source board. A pair of leads are provided on one surface of each substrate, and each lead is inserted into the corresponding end cap. within the pin and fixed to the inner wall of the pin; and

An LED drive circuit module is provided on the pair of substrates and is electrically connected to a lead on one of the substrates.